Zac Efron and Seth Rogen's new R-rated comedy "Neighbors" has taken up residence at the corner of gross-out humor and surprising sincerity. The movie stars Rogen and Rose Byrne as two young parents who move to the suburbs to raise their new baby, only to come into conflict with the hard-partying fraternity, led by Efron, that moves in next door.

Many critics are praising the film's blend of over-the-top antics and heart-on-its-sleeve wistfulness.

The Times' Betsy Sharkey wrote that "this raunchy unrooting of a settled suburban idyll exposes the considerable angst of emerging adulthood with a kind of scatological fervor designed to elicit oodles of inappropriate laughs. It succeeds."

She also cautioned, "Despite a strain of sweetness and considerable smarts, the film is a bit like 'Animal House' on steroids -- and with penis molds. If crude and lewd offend, beware."

USA Today's Claudia Puig agreed that the film is "not for the easily offended," but she also added that "somewhere amid all the vulgarity, the tender bond between Mac and Kelly [Rogen and Byrne] -- especially as they try to find their rightful place on the adult spectrum -- adds some surprising depth to this raunchy comedy."

Regarding the cast, Puig wrote that "Rogen and Byrne are appealingly wacky, their comic timing sharp. Efron, not known for his comedic talents, is hilarious as a sophomoric saboteur."

The San Francisco Chronicle's Mick LaSalle said "Neighbors" has all the hallmarks of a Nicholas Stoller movie: "the hilarious set pieces, the moments of social embarrassment and an undercurrent of seriousness that grounds and enhances the comedy and allows the actors to create rounded performances." He added, "Even as we laugh at the characters, we feel for them and recognize that the stakes are high."

The New York Times' A.O. Scott said the movie's "insightful glimmers ... provide a scaffolding of sincerity for the abundant drug-, sex- and body-based humor." He added, "'Neighbors' is not a great film and does not really aspire to be. It is more a status report on mainstream American movie comedy, operating in a sweet spot between the friendly and the nasty, and not straining to be daring, obnoxious or even especially original. It knows how to have fun. How very grown-up."

Ty Burr of the Boston Globe called the film "crassly funny, not entirely irrelevant" and said it "represents something of a watershed: the moment when all those Judd Apatow bad boys tremble on the edge of maturity, look back, and see the soulless face of a younger generation gaining on them."

Burr added, "Underlying all the condom jokes and bad behavior is something genuine: the anxiety that young people in a youth-obsessed culture can feel when they're finally and irrevocably called upon to be responsible." It's "bluntly funny" about married life and "surprisingly frank, too," about the uncertainty of post-college existence.

Not every critic enjoyed the party though. Ann Hornaday of the Washington Post said "Neighbors" "is less a coherent movie than a loosely assembled series of lewd jokes and punishing slapstick routines," and the New York Daily News' Joe Neumaier wrote, "During the movie's seemingly unending 97 minutes, the laughs are rare while the tedium is plentiful."